Fingolfen
Well-known member
- Build Rating
After building the Duo-Phase with the dual I/O (which could be run in single input / output configuration), I figured I'd tackle another pedal with the same functionality - the custom version of the ThorpyFx Heavy Water...
I unfortunately didn't get any photos of the individual boards before I started fully wiring them up (I blame enthusiasm and a lack of caffeine), so there's only the final gut shot at this point. I started with two South Obolon FX boards. Assembly is straightforward and the boards are very well laid out. As the boards are provided individually, you can build a single pedal in a 125B or even the smaller 1590B enclosure, or a dual pedal in a 1590BB. I went ahead and used a 1590BB2 because it provided me more depth to work with.
I ended up using a mix of resistors for this first build. I was running low on 10M ohm resistors, so I used a 5% carbon film resistor instead of my normal 1% metal film resistors. The rest of the resistors are, however a mix of Yageo and KOA Speer 1% 1/4W metal film resistors, though (with one left-over Vishay Dale thrown in to provide an additional visual differentiation between the "clean" and "dirty" sides so I didn't foul things up in final assembly). The film capacitors are all WIMA and KEMET, and the electrolytic capacitors are Nichicon. There's one OPA2134PA dual op amp on each board, and I've socketed them. Both boards have four 1N4148 diodes. The only real difference between the clean and dirty boards is the clean side uses two 1N747A zener diodes and the dirty side uses germanium diodes. I grabbed a couple of vintage 1N34A diodes I'd picked up from Pedalhacker once upon a time, but I'll likely experiment with others in the future.
I followed the same general wiring scheme for the four I/O jacks I used on the earlier Duo-Phase build. This arrangement works very well, and provides a lot of flexibility for dual pedal designs. I'd hoped to ground all four jacks directly to the PCBs, but there is only one additional ground connection on the board itself beyond those needed for power and switching (which would have been find if I was using single I/O). I therefore grounded the outputs to the input, and then the input to the board. Because you essentially have two pedals in one rather small enclosure, the wiring is a bit busy, but I tried to keep the lengths as short as possible.
I'd teased the enclosure art for this build previously on my Instagram page, but the Illustrator files never seem to do the final article justice. I decided to stick with the atomic theme of the original "Heavy Water" pedal name, and found a very cool piece of Spinosaurus clip art to create the Atomic Carnivore. I fleshed out the rest of the enclosure with some old nuclear patents and symbols. I'd hoped to use some mini chicken-head knobs for this build, but the Low 2 and Boost 1 knobs are just a bit close together to make that work, so I went with some other retro looking knobs instead.
In early tests everything seems to be functioning like the various demos online. The clean side is a nice clean boost, and the "dirty" side adds a fair amount of grit. Things get very interesting when you have both on at the same time - then you're pushing even a solid state amp into distortion territory, and the tone is really crisp without the mud you can get from some dedicated distortion pedals. I'm definitely going to be playing around a lot more with this one!
Original Blog Entry with extra preamble: https://steggostudios.blogspot.com/2022/12/another-combo-pedal-well-sort-of.html
I unfortunately didn't get any photos of the individual boards before I started fully wiring them up (I blame enthusiasm and a lack of caffeine), so there's only the final gut shot at this point. I started with two South Obolon FX boards. Assembly is straightforward and the boards are very well laid out. As the boards are provided individually, you can build a single pedal in a 125B or even the smaller 1590B enclosure, or a dual pedal in a 1590BB. I went ahead and used a 1590BB2 because it provided me more depth to work with.
I ended up using a mix of resistors for this first build. I was running low on 10M ohm resistors, so I used a 5% carbon film resistor instead of my normal 1% metal film resistors. The rest of the resistors are, however a mix of Yageo and KOA Speer 1% 1/4W metal film resistors, though (with one left-over Vishay Dale thrown in to provide an additional visual differentiation between the "clean" and "dirty" sides so I didn't foul things up in final assembly). The film capacitors are all WIMA and KEMET, and the electrolytic capacitors are Nichicon. There's one OPA2134PA dual op amp on each board, and I've socketed them. Both boards have four 1N4148 diodes. The only real difference between the clean and dirty boards is the clean side uses two 1N747A zener diodes and the dirty side uses germanium diodes. I grabbed a couple of vintage 1N34A diodes I'd picked up from Pedalhacker once upon a time, but I'll likely experiment with others in the future.
I followed the same general wiring scheme for the four I/O jacks I used on the earlier Duo-Phase build. This arrangement works very well, and provides a lot of flexibility for dual pedal designs. I'd hoped to ground all four jacks directly to the PCBs, but there is only one additional ground connection on the board itself beyond those needed for power and switching (which would have been find if I was using single I/O). I therefore grounded the outputs to the input, and then the input to the board. Because you essentially have two pedals in one rather small enclosure, the wiring is a bit busy, but I tried to keep the lengths as short as possible.
I'd teased the enclosure art for this build previously on my Instagram page, but the Illustrator files never seem to do the final article justice. I decided to stick with the atomic theme of the original "Heavy Water" pedal name, and found a very cool piece of Spinosaurus clip art to create the Atomic Carnivore. I fleshed out the rest of the enclosure with some old nuclear patents and symbols. I'd hoped to use some mini chicken-head knobs for this build, but the Low 2 and Boost 1 knobs are just a bit close together to make that work, so I went with some other retro looking knobs instead.
In early tests everything seems to be functioning like the various demos online. The clean side is a nice clean boost, and the "dirty" side adds a fair amount of grit. Things get very interesting when you have both on at the same time - then you're pushing even a solid state amp into distortion territory, and the tone is really crisp without the mud you can get from some dedicated distortion pedals. I'm definitely going to be playing around a lot more with this one!
Original Blog Entry with extra preamble: https://steggostudios.blogspot.com/2022/12/another-combo-pedal-well-sort-of.html
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